Stajpliylbdd(£ of the Amazon Valley. 51 



bus deflexis, caput amplectentibus. Scutellum transvcrsum, 

 apice conspicuo. Elytra prothorace longiora, apice trun- 

 cata. Mesosternum inter coxas intermedias longe pro- 

 ductum, parte producta elevata. Abdomen convexura, 

 conico-cylindrlcum, lateribus marginatum, basi fortiter 

 constrictum. 



The curious insect for wliicli I propose this generic 

 name is one of the most remarkable of the StaphjUnida 

 found by Mr. Bates. Unfortunately I have seen but a 

 single individual, so that I am able to give its characters 

 in only an incomplete manner. The head is small, de- 

 flexed, and much embraced by the angles of the thorax, so 

 that I have been quite unable to see the parts of the 

 mouth ; and although I have made a careful examination 

 ^vith the compound microscope, I do not feel quite sure 

 that the front tarsi may not have a minute basal joint. ^ I 

 cannot pronounce on its exact position a confident opinion, 

 but I believe it Avill idtimately be found allied to Dinarda, 

 possibly making an approach from that genus to the won- 

 derful Corotoca of Schiodte. 



Rey has recently considered the genus Dinarda as 

 forming of itself one of the eight primary divisions of the 

 AleocharidcB ; this isolated position he assigns to^ it in 

 consequence of the elytra being compressed and carinated 

 at the sides, which is "the case so fiir as he knows Avith no 

 other AleockaridcE. The Mijrmigaster singiilaris shows, 

 however, no trace of this peculiarity ; I myself consider 

 this character to be quite insufficient of itself to justify the 

 prominent isolation given to the two species of Dinarda 

 by the learned Frenchman, who actually makes, of the two 

 species of Dinarda, the first branch (branche, Dinar- 

 daires) of the Aleocharidce. 



1. Myrmicjaster sinyularis, n. sp. Rufo-picea, subni- 

 tida, antennis pedibusque testaceis, obsolete punctulata ; 

 thorace fortiter transverso ; elytris, hoc ter longioribus, 

 apicem versus subattenuatis. Long. \\ lin. 



Antennte formed as in the genus Dinarda, but much 

 more slender, and with their exserted sette longer; the 

 joints are closely packed, so that the divisions between 

 them are not striking; the 1st joint stouter and longer 

 than the 2nd ; the 2nd and 8rd small, the 2nd being the 

 longer of the two; from the 4th to the 10th each joint is 

 but slightly stouter than the foregoing one ; the 10th 



E 2 



